Release of Eicosanoids from Isolated Lungs of Guinea-pigs Exposed to Pure Oxygen: Effect of Dexamtethasone

The effect of dexamethasone on bradykinin-induced release of eicosanoids from isolated lungs of guinea-pigs exposed to pure oxygen (O2) is described. Pathological changes were induced in the lungs of guinea-pigs exposed to pure O2 for 72 and 96 h. Bradykinin-induced release of 6-oxo-PGF1 alpha and thromboxane B2 (TXB2) was increased in lungs from guinea-pigs exposed to 72 and 96 h of O2. Removal of PGI2 and PGE2 was not affected by the exposure to O2, but the removal of bradykinin was significantly reduced after 96 h of O2 exposure. Dexamethasone did not reduce bradykinin-induced release of eicosanoids from lungs of control animals, but it did inhibit the release from lungs of guinea-pigs exposed to O2. Dexamethasone had no effect on the metabolism of Bk by the inflamed lungs.